- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Thu, 12 Apr 2012 11:08:44 +0100
- To: public-rdf-dawg@w3.org
On 12/04/12 10:50, Polleres, Axel wrote: > Hi, > > </chair-hat> > > > just as I was stumbling over it something for the wish-list... > > We need datetime-difference for some use case. > Was that ever considered in previous discussions in the functions-library? Yes. 1/ You can do it by operator extension. 2/ The decision was not to require all of XSD (datatypes, functions) in core SPARQL. See also charter for LDP-WG. > I am looking at the XPath arithmetics delegation in Table "SPARQL Binary Operators" in Section 17.3 of the query doc, cf. www.w3.org/TR/sparql11-query/ > > > It's probably too much of a burden to add it now, but "nice-to have" for my use case would be Slippery slope! We would have to add required support for xsd duration hierarchy (xs:dayTimeDuration, xs:yearMonthDuration). And xs:g*? -- probably more generally useful. Next step is xsd:time ... (Disclosure: ARQ does g* and some of durations but not all arithmetic on datetimes - someone contributed the duration support) > > 1) delegating "-" > to > > op:subtract-dateTimes ( http://www.w3.org/TR/xpath-functions/#func-subtract-dateTimes ) > > For > > xsd:dateTime - xsd:dateTime > > > 2) delegating "+" > > to > > op:add-dayTimeDuration-to-dateTime FYI: Only applies to DT+dayTimeDuration, not the other way round. > > for either > > xsd:dateTime + xsd:dayTimeDuration > or > xsd:dayTimeDuration + xsd:dateTime > > > Best, > Axel Implementation burden for compliance. Personally, don't care - I'll add as much as users want. Andy
Received on Thursday, 12 April 2012 10:09:21 UTC